Jadaptive Maverick Synergy Server before 3.0.33 and 3.1.x before 3.1.7, and Maverick Legacy Server before 1.8.1, contain an authentication…
CVE-2026-127090
Jadaptive Maverick Synergy Server before 3.0.33 and 3.1.x before 3.1.7, and Maverick Legacy Server before 1.8.1, contain an authentication bypass vulnerability in SSH public key authentication that reuses cached key authorization decisions across usernames. Attackers holding a key authorized for one account can authenticate it, then send a signed SSHMSGUSERAUTHREQUEST with a different username on the same connection to log in as that account.
Assessment
- CVSS
- 8.7 (v4.0)
- Severity
- High
- Known exploited
- Not listed in CISA KEV
- Exploit availability
- Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
- Published
- 13 November 2026
- Last updated
- 13 November 2026
- Affected
- Jadaptive · Maverick Legacy Server · Maverick Synergy Server
- Assigner
- VulnCheck
CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
At the source
References
- https://jadaptive.com/security/advisories/JADAPTIVE-SA-2026-001
- https://github.com/sshtools/maverick-synergy/commit/f7d23182cce985e21048215e96395881295cb0bd
- https://store.jadaptive.com/app/api/releases/changes/01d04a39-0f05-4bae-842e-d2f1acc16985
- https://store.jadaptive.com/app/api/releases/changes/ff71bdcf-a2a2-47e0-af5a-22e15af1dfa4
- https://github.com/sshtools/maverick-synergy/blob/3.1.4/maverick-base/src/main/java/com/sshtools/common/auth/PublicKeyAuthentication.java#L82-L100
- https://github.com/sshtools/maverick-synergy/blob/3.1.4/maverick-synergy-server/src/main/java/com/sshtools/server/AuthenticationProtocolServer.java#L185-L200
- https://www.vulncheck.com/advisories/jadaptive-maverick-synergy-server-before-3.0.33-and-3.1-x-before-3.1.7-and-maverick-legacy-server-before-1.8.1-ssh-public-key-cross-user-authentication-bypass
Community proofs of concept
No community proof of concept yet. If you have one for a published vulnerability and the right to share it, add it below — it will appear here once reviewed.
Submit a proof of concept
Only for publicly disclosed vulnerabilities, and only material from testing you were authorised to perform. This platform does not buy, sell, or broker exploits — see earning from vulnerability research for legitimate bounty programs. Submissions are reviewed before they appear. Text only; do not include live credentials, personal data, or anything targeting systems you are not permitted to test.
Query this programmatically
Agents can read this through the MCP endpoint, or over HTTP:
curl https://cve.zerocrew.in/api/cve/CVE-2026-127090